A NEW ASTRONOMY 



$1-3° 



By DAVID TODD, M.A., Ph.D., Professor of Astron- 

 omy and Navigation, and Director of the Observatory, 

 Amherst College. 



ASTRONOMY is here presented as preeminently a 

 science of observation. More of thinking than of 

 memorizing is required in its study, and greater emphasis 

 is laid on the physical than on the mathematical aspects of 

 the science. As in physics and chemistry the fimdamental 

 principles are connected with tangible, familiar objects, and 

 the student is shovyn how he can readily make apparatus to 

 illustrate them. 



^ In order to secure the fullest educational value astronomy 

 is regarded, not as a mere sequence of isolated and imperfectly 

 connected facts, but as an inter-related series of philosophic 

 principles. The geometrical concept of the celestial sphere is 

 strongly emphasized; also its relation to astronomical instru- 

 ments. But even more important than geometry is the philo- 

 sophical correlation of geometric systems. Ocean voyages 

 being no longer uncommon, the author has given rudimental 

 principles of navigation in which astronomy is concerned. 

 ^ The treatment of the planets is not sub-divided according 

 to the planets themselves, as is usual, but according to special 

 elements and features. The law of universal gravitation is 

 unusually full, clear, and illuminating. The marvelous dis- 

 coveries in recent years and the advance in methods of teach- 

 ing are properly recognized, while such interesting subjects 

 as the astronomy of navigation, the observatory and its 

 instruments, and the stars and the cosmogony receive particu- 

 lar attention. 



^ The illustrations demand special mention; many of them 

 are so ingeniously devised that they explain at a glance what 

 many pages of description could not make clear. 



AMERICAN BOOK COMPANY 



(•8i) 



